In 2010, a British television crew filming Darkest Secrets ventures into a remote Siberian forest known for the 1998 deaths of thirty-four unidentified people. The team includes Kate Hansen Kate Hansen, the host, Matt Hurst Matt Hurst, the cameraman, and David Hamilton David Hamilton, the tech. They are joined by Ruth Peacock Ruth Peacock, a psychic, and Yuri Levkov Yuri Levkov, a Russian author, who bring different perspectives to the expedition. As the night closes in, Ruth’s sensitivity intensifies, and she begins to receive voices that speak in Russian, hinting at a violent past buried in the woods. The group presses on, drawn by Ruth’s visions toward a growing sense that eastward lies something larger and more dangerous than a simple haunting.
Guided by Ruth’s visions, the troupe heads toward what Yuri believes is an abandoned facility tied to the forest’s grim history. A cold dread settles over the party as Ruth witnesses more images of soldiers and prisoners, and she urges perseverance despite the growing disquiet. When they arrive at the facility’s threshold, distant, echoing screams drift through empty corridors, and Ruth cautions against entering, though Kate pushes them to continue. Inside, they discover cages, sealed cells, and the remnants of a site that once treated intimidation as a form of science. Ruth again hears Russian voices, and Yuri translates them as warnings to turn back. In one room, Ruth is overwhelmed by visions of torture, and she explains that the victims were psychics like herself. A hostile presence seems to twist the air, feeding off their fear, and Ruth identifies the source as [Mischka], a dead prisoner subjected to brutal experiments. The moment Mischka turns aggressive, the group retreats, realizing that David has vanished.
Back in a control room, they review the footage and catch fleeting glimpses of both Mischka and David. Matt insists they locate David, while Ruth, exhausted, urges rest. Before sleep, Ruth hints that Yuri has been here before, a claim Yuri confirms by admitting he knew about the facility and its history of brutal experiments on psychics—yet he needed to know if Ruth could truly find it. When Kate hears David’s voice, she and Matt venture deeper to search for him, while Yuri keeps watch over Ruth as she sleeps. The tension escalates when Mischka ambushes and kills David in front of Matt and Kate, forcing them to flee back to the control room. There, Yuri wrestles Ruth away from danger and demands that she help him release the spirit of his lost girlfriend, whom he believes was slain in this place.
As they descend further, Mischka’s hostility grows more pronounced. Yuri glimpses the ghost of his girlfriend, but when he approaches, Mischka savagely defeats him. Ruth orders Matt and Kate to leave, and she tries once again to contact Mischka to calm the restless energy of the facility. Just as they’re about to depart, Kate hesitates and decides to turn back to aid Ruth, with Matt reluctantly following. They locate Ruth collapsed in Mischka’s cell, where she explains that she has helped Mischka cross over and that the facility is now stabilized. Relieved, Kate and Matt begin to gather equipment, but Kate spots troubling footage of Ruth’s struggle with Mischka and grows uneasy about Matt’s safety. The grim truth reveals itself when Matt is found dead, and Ruth, now possessed by Mischka, kills Kate. In the end, Kate realizes that she and the remaining crew are doomed to wander the halls of the facility forever, joining the ghosts who linger in its corridors.
